This project consists of four studies with the following objectives: 1. To define those culture conditions that induce or prevent chromosomal instability, DNA damage and "spontaneous" neoplastic transformation of rodent cells in culture as compared with human cells. 2. To establish whether the topography of neoplastic and nonneoplastic cells in culture differs and is influenced by cell cycle. 3. To analyze and explain differences in locomotion of nonneoplastic and neoplastic cells of common origin. 4. To develop and evaluate rapid tests for neoplastic transformation in vitro. BIBLIOGRAPHIC REFERENCES: Sanford, K.K., Handleman, S.L., and Jones, G.M.: Morphology and serum dependence of cloned cell lines undergoing spontaneous malignant transformation in culture. Cancer Res. 37: 821-830, 1977. Parshad, R. and Sanford, K.K.: Oxygen and light effects on chromosomal aberrations in mouse cells in vitro. Exper. Cell Res. 104: 199-205, 1977.